Originally Posted by Parabola
I suppose the idea is to help your eye find the rear aperture but as you are meant to be looking through the rear aperture and trying to pick up the front bead and the target I am not convinced that the bright ring would assist.

Agreed. It would do just the opposite.

If you are familiar with a Hadley eyecup - made by several manufacturer's - they are adjustable for light levels. Whether there is one that would fit your sight, I don't know, but they are common on the firing line at a BPCR/BPTR event.

_________
BrentD, (Professor - just for Stan)
=>/

[Linked Image from i.imgur.com]